Education

B.S., University of Rochester, Rochester, NY

Ph.D., Duke University

Research Interests

Our laboratory interests center on the controls of phytoplankton growth and the factors that control the fate of the photosynthetic material in the surface layer of the ocean. To that end we are interested in the interactions between various pools of organic carbon in the surface of the ocean, including dissolved organic carbon, dissolved inorganic carbon, total particulate organic carbon, and living matter (bacteria, micro- and mesozooplankton). We have primarily focused on processes occurring in the Ross Sea, Antarctica, largely because the Antarctic is known to be critical in controlling the marine carbon cycle due to its interaction with the atmosphere and its role in producing deep water. We quantify the contribution of phytoplankton to the particulate organic carbon pool using a number of procedures, and then analyze the fluxes to and from this pool. I have a strong interest in the role of phytoplankton assemblage structure on the vertical flux of material from the ocean's surface, and also have a strong interest in the role of iron in structuring the ocean's phytoplankton productivity and growth.

I also have developed an interest in applying new technology to oceanography, specifically the use of gliders in the Antarctic. We have had one project that investigated the spatial coherence of deep-water intrusions onto the shelf in the Ross Sea with surface phytoplankton blooms, and have another one that will look at the linkage in space and time of phytoplankton blooms, relative abundance of macrozooplankton and small fish, and penguin foraging. This project seeks to demonstrate that penguin “hotspots” of foraging develop in response to prey aggregations that can be identified by physical factors. As part of that we also will begin the formation of a full food web model of the Ross Sea.

Finally, I have been working off the coast of Vietnam and have investigated the ecophysiology of a harmful algal bloom species (Phaeocystis globosa) that blooms there. The species has a number of unusual characteristics which greatly influence its life history. Although the project has ended, we hope to continue this work in the near future.

I have recently been appointed as a 1000 Talents Professor at Shanghai Jiao Tong University and am in residence in China for approximately 6 months per year.